LT3688 LINER [Linear Technology], LT3688 Datasheet - Page 3

• Manufacturer Part Number: LT3688
• Description: Dual 800mA Step-Down Switching Regulator with Power-On Reset
• Manufacturer: LINER [Linear Technology]

ELECTRICAL CHARACTERISTICS
junction temperature range, otherwise specifi cations are at T
SYMBOL
V
t
t
t
t
t
RST
WDU
WDL
WDTO
UV
UV
PARAMETER
V
Quiescent Current from V
Quiescent Current from BIAS
FB Voltage
FB Pin Bias Current
FB Voltage Line Regulation
Switching Frequency
Minimum Off-Time (Note 4)
Switch Current Limit (Note 5)
Switch V
Switch Leakage Current (Note 8)
DA Current Limit
Boost Schottky Reverse Leakage
Minimum BST Voltage above SW
BST Pin Current
EN/UVLO Threshold Voltage
EN/UVLO Input Current
Threshold Current Hysteresis
RUN/SS Pin Current
RUN/SS Switching Threshold
SYNC Threshold Voltage
Reset Threshold
Reset Timeout Period
Watchdog Window Upper Boundary
Watchdog Window Lower Boundary
Watchdog Timeout Period
RST Output Voltage Low
UV Detect to RST Asserted
WDI Input Threshold
WDI Input Pull-Up Current
WDI Input Pulse Width
WDE Threshold Voltage
WDE Input Pull-Down Current
WDO Output Voltage Low
IN
Undervoltage Lockout
CESAT
IN
CONDITIONS
V
V
V
V
V
V
V
5V < V
R
R
V
DC = 15%
I
V
I
V
V
V
% of FB Voltage, V
C
C
C
C
I
I
V
V
I
I
SW
SW
SINK
SINK
SINK
SINK
EN/UVLO
BIAS
BIAS
EN/UVLO
BIAS
BIAS
FB
BST
BIAS
EN/UVLO
EN/UVLO
RUN/SS
POR
WDT
WDT
WDT
FB
WDE
T
T
= 20k, V
= 110k, V
= 0.800V
= 0.8A
= 0.8A
Set to 0.680V
= 12V
= 2.5mA, V
= 100μA, V
= 2.5mA
= 100μA
= 4700pF
= 0V
= 1000pF
= 1000pF
= 1000pF
= 1.2V
= 5V, Not Switching
= 0V, Not Switching
= 5V, Not Switching
= 0V, Not Switching
IN
= 0V
< 36V
= 1.35V
= 1.15V
= 0.3V
= 0.3V
The
BST
BST
A
= 12V
l
FB
FB
= 12V
= 25°C. V
denotes the specifi cations which apply over the full operating
FB
= 0.6V
= 0.6V
Falling
IN
= 12V, unless otherwise noted. (Note 3)
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
0.790
0.784
1.85
1.15
–1.4
21.2
MIN
0.15
460
300
1.2
0.9
2.5
2.5
0.4
0.8
0.4
0.4
88
18
3
4
0.800
0.002
–0.01
0.01
0.01
0.01
2.15
1.25
–2.8
23.5
1.25
0.01
0.95
0.65
0.01
TYP
235
155
500
115
280
3.5
2.1
1.7
1.2
0.3
3.7
0.8
0.8
2.5
0.2
3.5
0.2
65
–5
–3
15
90
20
10
–2
4
0.810
0.814
MAX
2.35
1.35
25.8
105
310
200
–20
–50
540
180
3.8
2.2
1.6
2.5
5.5
1.3
1.6
0.4
0.3
1.3
0.4
0.3
LT3688
–1
25
–4
92
22
30
1
1
2
6
1
1
UNITS
3
MHz
3688f
%/V
kHz
mV
mA
ms
ms
ms
ms
μA
μA
μA
μA
μA
μA
nA
μA
μA
μA
μA
μA
μA
μA
μA
ns
μs
ns
%
V
V
V
A
A
V
V
V
V
V
V
V
V
V
V